It seems Fernando Alonso and McLaren expect Italian Grand Prix winner Lewis Hamilton to be the Spaniard's strongest competition in the final seven races of the 2012 world championship and, in McLaren's case, beyond that, for the team admit that they have no Plan B should he really move to Mercedes next year.

"At the moment McLaren have won the last three Grands Prix and they are in top form," Alonso said. "I think from Jerez in winter testing, Lewis was the driver that I respect more and we're still here; 13 races afterwards we are first and second in the championship. It will be tough until the end."

The McLaren chief executive, Martin Whitmarsh, expects his driver to stay. "I haven't given Plan B any thought," he said after the 2008 world champion scored his first victory at Monza. "We want Lewis to stay, and we want him to stay if he wants to stay. But when you are trying to win a championship, you have a number of priorities. You divide your time, energy and focus on those things – one of them is making the car faster, better; another is dealing with all the operational issues to make sure you don't make mistakes, and another is dealing with your own drivers. Rightly or wrongly, I haven't spent a lot of energy on the latter subject."

Hamilton's manager, Simon Fuller, has had talks with Mercedes, provoking speculation from BBC pundit Eddie Jordan that a move is imminent. Relations between Jordan and Whitmarsh became further strained when in an interview with the BBC, Whitmarsh said: "Any comment that begins with the words, 'Eddie Jordan understands…' is fundamentally questionable." Whitmarsh is keen to get the Hamilton situation sorted quickly and said he plans to speak with Fuller prior to the Singapore Grand Prix later this month. "As you know, we deal with management companies, not directly with drivers, which is the way of the world – or the way of the drivers – so I'm sure we'll be having those conversations very shortly," he said.

Speculation suggests McLaren may be offering Hamilton as little as $7.5m (£4.6m) compared with his current salary of $15m, and that Mercedes have offered him $12m. But sources in Germany insist Michael Schumacher will stay with the team, leaving no opening for Hamilton.

Meanwhile, Jenson Button has claimed he won't be riding shotgun for his team-mate. Button is 78 points adrift of Alonso compared to Hamilton's 37, but said: "I'm still going to try and win every race from here on in."